#1 ADU Contractor in Bellflower
Custom Builds by Horizon Remodeling

Finding the right adu contractor in Bellflower means understanding both state law and the specific conditions on your parcel before a single line gets drawn. California consolidated its ADU statutes into Government Code sections 66310 through 66342 in 2024, and those rules were updated again on January 1, 2026. Under the current framework, square footage is measured as interior livable space, and the reviewing agency has 15 business days to determine whether your application is complete, followed by 60 days to approve or deny it. Approval is ministerial, meaning no public hearing and no discretionary design review stand between a complete application and a decision.

For any property within city limits, that application goes to the City of Bellflower Building and Safety Division. No unusual local overlay applies here, so what drives the review is the state building code and the age and configuration of your house. That is worth knowing because the rules change from one of Los Angeles County’s 88 incorporated cities to the next, even when the underlying state statute stays the same. A permit counter in a neighboring city is a different counter with different staff and sometimes different interpretations.

A county-level point is also worth keeping in mind. The county’s own ADU ordinance, amended in July 2025, was found non-compliant with state law by the California Department of Housing and Community Development in December 2025. Among other findings, it caps detached ADUs on a multifamily lot at two, where state law allows up to eight. That ordinance governs unincorporated territory, not incorporated Bellflower, but it is a useful reminder that a local handout is not always current with the statute.

The lot itself decides most of what follows. Bellflower was largely built out during the 1940s and 1950s, when the population surged from roughly 11,000 to 44,000 in a single decade before the city incorporated on September 3, 1957. The result is a city of single-story postwar tract houses on slabs, densely packed, with about six in ten units renter-occupied. That housing stock shapes where a detached unit can physically sit, how far utilities have to run, and whether a garage conversion or a new detached build makes more sense for your situation. We walk the parcel and check setbacks, grade, equipment access, and utility routes before drawing anything.

State law provides several protections regardless of where your parcel sits. A local agency cannot cap an ADU below 850 square feet of interior livable space, or below 1,000 square feet if the unit has more than one bedroom. Side and rear setbacks cannot exceed four feet. Owner-occupancy cannot be required as a condition of building an ADU. Adding a unit cannot trigger a fire sprinkler retrofit of the main house. And there are no impact fees on a unit of 750 square feet or less.